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DOE announces NEPA exclusion for advanced reactors
The Department of Energy has announced that it is establishing a categorical exclusion for the application of National Environmental Policy Act (NEPA) procedures to the authorization, siting, construction, operation, reauthorization, and decommissioning of advanced nuclear reactors.
According to the DOE, this significant change, which goes into effect today, “is based on the experience of DOE and other federal agencies, current technologies, regulatory requirements, and accepted industry practice.”
Sergey V. Konovalov, Sergey V. Putvinsky
Fusion Science and Technology | Volume 18 | Number 3 | November 1990 | Pages 397-402
Alpha Particles in Fusion Research | Technical Paper | doi.org/10.13182/FST90-A29273
Articles are hosted by Taylor and Francis Online.
The influence of static helical perturbations on high-energy ion motion in tokamaks is investigated. Numerical solutions of drift motion equations are in good agreement with analytic estimations of the critical amplitude value that is sufficient for destruction of drift surfaces. Three types of perturbations are considered: large-scale helical modes with wide regions of localization comparable with the plasma column radius, small-scale modes localized near the resonant magnetic surfaces, and balloon-like modes. For all three cases, high perturbation amplitudes are needed for destruction of drift surfaces. The static helical perturbation does not appear to lead to noticeable high-energy particle losses in tokamaks until the perturbation amplitude exceeds the value sufficient for magnetic surface destruction.